The present invention generally relates to a storage control system and a storage control method, and in particular relates to a storage control system connected to a host system and which stores data to be sent to and received from the host system in an HDD (Hard Disk Drive) as a storage medium based on a RAID (Redundant Arrays of Inexpensive Disks) mode, and to a storage control method thereof.
As this kind of storage control system, for instance, known is a type comprising a drive having a rotating storage device for storing data, and a storage controller interposed between the drive and a host system and which controls the transfer of data between the drive and the host system (refer to Japanese Patent Laid-Open Publication No. H11-191037; “Patent Document 1”).
Patent Document 1 describes correction copy of recovering all data of a failed drive from the remaining drives of an ECC group (RAID group) and copying such data to a spare disk drive when a failure occurs in a disk drive and becomes inoperable.
Further, as a storage control system comprising a spare disk drive, proposed is a type that recovers data from the other disk drives configuring RAID when one of the disk drives configuring RAID fails, and recovering the operation from a degenerate state of RAID to a normal access state where all disk drives configuring RAID are operable (refer to Japanese Patent Laid-Open Publication No. 2002-297322).
Further, proposed is a storage control system comprising a disk array controller, a disk drive connected to the disk array controller via a drive interface and for storing a plurality of data arranged in an array, and a data backup apparatus for backing up data stored in the disk drive, wherein a plurality of disk drives are used as spare disk drives, the remaining disk drives are used as data/parity disk drives for storing data and the like, and using the spare disk drives as the data/parity disk drives in substituted for failed data/parity disk drives (refer to Japanese Patent Laid-Open Publication No. H6-139027).
In other words, with conventional storage control systems, when a failure occurs in a disk drive, correction copy is started, and the maintenance staff notified of the start of correction copy confirms the completion of correction copy, thereafter replaces the failed disk drive with a normal disk drive, and, after such replacement, the maintenance staff issues a command to the storage control system to copy back the stored information of the spare disk drive to the replaced disk drive.